Portable apparatus for identifying electric conductors



Nov. 3, 1925- W. J. MAHA'N PORTABLE APPARATUS FOR IDENTIFYING ELECTRICCONDUCTORS Filnd Jan. 23. 1.924

3 SheetS-Shiit l Nov. 3,1 5. 1,560,278

-w. J. MAHAN PORTABLE APPARATUS FOR IDENTIFYING ELECTRIC CONDUCTORSFiled Jan. 23. 1924 3 Sheets-Shed, 2

Nov. 3,1925. 1,560,278

W. J. MAHAN PORTABLE APPARATUS FOR IDENTIFYING ELECTRIC CONDUCTORS FilndJan. 25, 1924 3vSheet8-Sh0 ii 5 v drawings constitute Patented Nov. 3,1925.

UNITED STATES 1,560,278 PATENT OFFICE.

WILLIAM J". MAHAN, OF NEW HAVEN, CONNECTICUT.

PORTABLE APPARATUS FOR IDENTIFYING ELECTRIC CONDUCTORS.

. Application filed January 23, 1924.; Serial No. 688,045.

To all whom it may concern:

Be it known that I, WILLIAM J. MAHAN, a citizen of the United States,residing at New Haven, in the county of New Haven and State ofConnecticut, have invented a new and usefulImprovement in PortableApparatus for Identifying Electric Conductors; and I do hereby declarethe following, when taken in connection with the accompanying drawingsand the characters of reference marked thereon, to be a full, clear, andexact description of the same, and which said part of this application,and represent in- Fig. l a schematic view,'showing an electric lightingcircuit with thetwo units of my improved apparatus in position forapplication. thereto.

Fig. 2 a view in central, longitudinal section of the unit A. of myapparatus.

Fig. 3 a corresponding view of the unit B 7 thereof.

Fig. 4 a plan view of an adapter for cartrige-fuse sockets. I

Fig. 5 a perspective view of an adapter for bus-bar connections. Fig. 6a plan view of a flexible connector provided with spring-clips.

Fig. 7 a diagrammatic view of a circuit.

showing my two units A and B coupled thereinto, with the wiringcorrectly connected to the outlet.

Fig. 8 a similar View, with the exception that the wiring is incorrectlyconnected.

Fig. 9 a diagrammatic view of the circuit in Ithe unit B when being usedas a flashig t.

My invention relates to an improved portable apparatus for identifyingelectric conductors wherever that may be desired, and for whateverpurpose, the object being to produce a simple, convenient and reliabledevice for the purpose indicated.

Vith these ends in view, In invention consists in a portable apparatusor identifying electrical conductors characterized by two independentlyorganized but co-operative units, each having a source of electricalenergy and two terminals adapted to be .connected into a circuit andsome approved form of electrically-operated signal brought into playbythe co-action in series ofthe energies of the two units.

My invention further consists in an apparatus of the character abovedescribed, in

which one of the units is organized to operate as aflashlight. 1 v

. My invention further consists in an apparatus having certain detailsof construction and combinations of parts as will be hereinafterdescribed and pointed out in the claims.

Forthe convenlence of illustration and description, I have shown myimproved apparatus as constructed for identifying the conductors of anelectric lighting circuit, though I would have it understood that myinvention is not limited to such a construction, since modifications ofit will be required to adapt it for usein other situations, such astesting telephone, telegraph and signaling-wires.

In carrying outmy'invention, as herein shown, I employ twoindependenty-organized but co-operative units, each functioning as asource of electrical energy, and adapted, when inserted into the circuitto be tested, to act in series to operate an electric indicator,whatever its character, which 'shall serve to indicate whether thecircuit is coupled up right or wrong. For transportation, these twounits are packed and carried together, but when in actual use, onebecomes stationary, While the other is moved from point to point foridentifying purposes. It'will be convenient, therefore, to

taining two dry-battery cells 12-12. The i outer end of the said casingmounts a cylin: drical plug 13 of insulating material having a molded,helical thread-14c adapting it'to be screwed into a standard screw-shell15.-

The plug 13 is held in place by an insulating washer 16, located withinan annular retaining-flange 17 formed by turning inward, at a fightangle, the outer edge of the casing 10, as clearly shown in Fi 2, and

inched between the said plug an washer by the binding action ofa longshouldered rivet 18, formed at its flanged outer end with a threadedscrew-hole '19, the purpose of which will be described later on,the'said furnished with a spring-clip 22-, engaged by the inner end ofa'short length of flexible wire 23, the opposite end of which carries aninsulating plug 24 having a molded, helical screw-thread 25 andfurnished with a centrally-arranged which the wire 23 is attached by abindingnut 27.

The traveling unit'B has a tubular. casing 28 receiving two drysbatterycells 2929. At its inner or handle end,'the casing 28 is threaded forthe reception of a threaded cap 30, mounting a lens 31 closing in the.

reflector 32 of a standard flashlight bulb 33, the threaded stem ofwhich is screwed into the threaded shank of the reflector, the shank ofwhich, inturn, isscrewed'into thelong threaded sleeve 34, of acontact-ring 35 carrying an annular body 36 of insulating material, inwhich is' embedded a resistance-coil 37, one end of whichis attached tothe said ring, while its other end is attached to a contact-band 38,embracing the said body 36 of insulating material. The

' said contact-ring 35 and band 38 are alternately engaged by theinwardly-extending spring-arm 39 of a double-throw slidingswitch 40mounted in the usual manner in the casing 28. The said switch alsocarries 45 of the cap 43.

a forwardly-extending spring-arm 41, the outer end of which engages, onoccasion, with a metallic washer 42 carried by a threaded cap 43 screwedupon the threadedouter end of the casing 28, the said washer 42 beinginsulated from the cap 43 by an insulating washer 44 bearing upon theinner face of the inwardly turned, annular flange The said flange 45 isclamped between the washer 44 and the inwardly-turned flange 46' of asheet-metal contact-sleeve 47, encasing a cylindrical plug 48 ofinsulating materialsecured to the cap 43 by means'of a longcontact-rivet 49, furnished at its outer end with a contactflange 50.The inner end of the rivet 49 passes through the washers-44 and 42 andthrough the inner end of a spring 51, upon which it is swaged, wherebythe parts being described are all drawn together and secured to the cap43. The said spring 5.1 acts through the outer cell 29 to maintain theinner cell 29 in engagement with the lamp 33, as required.

It may now beassumed that it is. required, for one reason or another, toidentify a conductor in its various ramifications in a given lightingcircuit. Let it be further. supposed contact-screw 26, to-

that the conductor C is the conductor which,

in its various ramifications, it is desired to distinguish from itsfellow conductor D.

In the first place, the plug 14 of the socalled stationary unit A isscrewed into the plug-fuse receiving screw-shell '15,, to which theconductor 0 is connected, whereby its contact-rivet 18 is brought into-engagement with the center-contact 20., The insulating plug 25 of theunit A is now 26 into engagement with the center-contact 53 thereof. Thetwo fuse-plug sockets abovedescribed are of standard construction' andmounted in the porcelain block 54.

screwed into the screw-shell 52 of the com- The complementary so-calledtraveling unit B is now inserted into the outlet tobe tested, so as tobring its rivet 50 into contact with the center-contact thereof, and itscontact-sleeve 47' into engagement with the threaded screw-shellthereof, the. switch 39 having been moved into the position in -whichiti s shown in F igs.3, 7 and 8. The

conductor C ofian electric lighting circuit of the character-shownshould beconnected with the screw-shell of the outlet, to comply withcertain safety requirements of the national.electrical code, fromwhichit follows that the conductor D is connectedwith the center-contactthereof. I

The units A and B having been positioned as described, if the conductorC is connectedwith the screw shell of the outlet as required, ratherthan with the center-contact thereof, a circuit will be closed throughthe batteries of the two units, which will operate, in

series, to light the bulb33 through the resistance-coil 37, whichprevents the double set of batteries from burning out the bulb. Thelighting of the lamp in this manner in.-- dicates to the circuitinspector that the conductors are properly connected, as shown in Fig. 7.If, on the other hand, the conductors O and D are improperly connectedor crossed, as shown in Fig. 8, withthe conductor C leading to thecenter-contact of the outlet, the dry-battery cells 12 and 29 will buckeach other, as the common phrase is, or nullify each-other, so that thelamp will not be lighted, and hence no signal will be given. In otherwords, the absence of a signal, under the circumstances, indicates thatthe connections in; the outlet must be transposedzor thatithe circuit isincomplete. In this manner, all of the outlets, in any given electricalcircuit, are successively tested, the unit A being left, as heretoforedescribed, in the fuse-block 54, while the unit I B, whichhas beendesignated as the travelingaunit, is moved on from outlet to outlet,until all the outlets in the particular circuit have been tested; Itwill be understood that the answer of the test takes place immediatelyupon the insertion of the traveling unit 13 into the outlet, so that thetesting of the outlets may be done rapidly. While the traveling unit Bis being moved from outlet to outlet, it may, if desired, be used as aflashlight, for which purpose its switch 39 is moved back into theposition in which it is shown in Fig. 9, whereby its battery 29 iscoupled into a local circuit through the bulb 33, the resistance-coil 37being now out out of the circuit to the lamp by moving the switch asdescribed. The adaptation of the traveling unit to be used as aflashlight is a matter of great convenience, as these inspections mustoften be carried on of necessity,

in the dark.

In case the circuit to be tested is equipped with so-called cartridgefuses, instead of screw-plug fuses, a metallic adapter 57, having thegeneral form and size of a standard cartridge fuse and provided with a.

screw-stud 58, is employed, its said stud being screwed into the hole 19of the rivet 18 of the unit A, whereby the same is adapted to be appliedto standard cartridge-fuse sockets. Under such circumstances, theconnector 23 is disengaged from the clip 22 of the unit A and replacedby a connector of the type shown in Fig. 6, comprising, as shown, amember 59 for engagement with the clip 22 and a flexible conductor 60,having branches til-61, carrying clips 6262, one of which will beclipped upon the fuse socket of a conductor corresponding to theconductor D. The other clip adapts such a connector to be used intesting three-wire and bus-bar installation circuits.

In Fig. 5 I have shown a coupling-plate (33 having a screw-stem (3dadapted to be screwed into the hole 19 of the rivet 18, the plate 63having a slot 65 for co-action with the bus-bar screws of a circuitequipped with bus-bars of standard construction. The modifications ofFigs. 5 and 6 show the units A and B are not limited to usein testingcircuits having screw-shell plug-sockets.

It is apparent that my improved apparatus might be constructed andconnected on the principal of having a signal given, such as bythelighting of a lamp, when the test showed an improper connection ofthe conductors to the outlets, instead of a proper connection thereof,as'herein illustrated, this being merely a matter of choice, and wouldbe effected by differently connecting the batteries in their cases, asreadily understood by any electrician. Furthermore, the

. signal chosen may be a light, a buzzer or a bell, or anyelectrically-operated signal, whether visible or audible, these beingdetails comprehended by my invention, which is broadly characterized bythe use of two indcpendently-organized but complementary units, eachhaving a source of electric energy and each having two terminals adaptedto be connected into a circuit and having some approved form ofelectrically-operated signal brought into play by the co-action 'of theenergies of the two units.

I claim:

1. A portable apparatus for identifying electric conductors, comprisingtwo indc pendcntly-organized, physically seperate complementary units,each having a separate source of electric energy and each having twoterminals adapted to be connected into a circuit, and the said apparatusalso comprising an electrically-operated signal brought into play onlyby the co-action in series of the electric energy of the physicallyseparate two units.

2. A portable apparatus for identifying electric conductors, comprisingtwo indc pendently-organized, complementary units, each having a sourceof electric energy and each having two terminals adapted to be connectedinto a circuit, and also compris ing an electrically-operated signalbrought spectively engage with the center-contact and screw-shell of astandard socket when inserted thereinto.

3. A portable apparatus for identifying electric conductors, comprisingtwo independentlv-organized, complementary units, each having a sourceof electric energy and each having two terminals adapted to be connectedinto a circuit, and also comprising an electrically-operated signalbrought into play only by the co-action in series of the electric energyof the two units, the terminals of one unit being positioned torespectively engage with the center-contact and screw-shell of astandard socket when inserted thereinto, and the other unit having aterminal, bv means of which it is supported in a fuse-socket and havinga flexibly-mounted terminal for engagement with its companionfuse-socket.

4:. A portable apparatus for identifying electric conductors, having twoindependently-organized, complementary units, each having a source. ofelectric energy, and each having two terminals adapted to be connectedinto a circuit, one unit carrying an electric bulb adapted to be lightedby the two units, a resistance interposed between energy of the twounits, one of the said units.

being provided with a center-contact terminal for co-action with thecenter-contact of a standard screw-shell socket, and also rovided with acontact-band concentric 20 with the said terminal for engagement withthe interior wall of the screw-shell of the said socket.

7. A portable apparatus for identifying I electric conductors,comprising two independently-organized, complementary units, each havinga tubular casing and'a dry-battery cell located therein and each unithaving two terminals adapted to be connected into a circuit, one unithaving a terminal adapted to support it in a fuse-socket and the otherunit having terminals positioned to respectively engage with thecenter-contact and screw-shell of a standard socket, and also having anelectrically-operated signal brought into play by the co-action inseries of the cells of the two units.

In testimony whereof, I have signed this specification.

WILLIAM J. MAI-IAN.

